package study.springcloud.gateway.support.cros;

import lombok.extern.slf4j.Slf4j;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.HttpStatus;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.web.server.WebFilter;
import reactor.core.publisher.Mono;

@Slf4j
@Configuration
public class _2_CorsConfig {

    private static final String ALL = "";

    private static final String MAX_AGE = "";

//    @Bean
    public WebFilter corsFilter() {
        return (exchange, chain) -> {
            ServerHttpRequest request = exchange.getRequest();
//            if (!CorsUtils.isCorsRequest(request)) {
//                return chain.filter(ctx);
//            }
            HttpHeaders requestHeaders = request.getHeaders();
            ServerHttpResponse response = exchange.getResponse();
            HttpMethod requestMethod = requestHeaders.getAccessControlRequestMethod();
            HttpHeaders headers = response.getHeaders();
            headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_ORIGIN, requestHeaders.getOrigin());
            headers.addAll(HttpHeaders.ACCESS_CONTROL_ALLOW_HEADERS, requestHeaders.getAccessControlRequestHeaders());
            if (requestMethod != null) {
                headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_METHODS, requestMethod.name());
            }
            headers.add(HttpHeaders.ACCESS_CONTROL_ALLOW_CREDENTIALS, "true");
            headers.add(HttpHeaders.ACCESS_CONTROL_EXPOSE_HEADERS, ALL);
            headers.add(HttpHeaders.ACCESS_CONTROL_MAX_AGE, MAX_AGE);
            if (request.getMethod() == HttpMethod.OPTIONS) {
                response.setStatusCode(HttpStatus.OK);
                return Mono.empty();
            }
            return chain.filter(exchange);
        };
    }


}
